// Copyright (c) 2026 Probo Inc <hello@probo.com>.
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
// SOFTWARE.

package oidc

import (
	"context"
	"fmt"
	"time"

	"go.gearno.de/kit/log"
	"go.gearno.de/kit/pg"
	"go.probo.inc/probo/pkg/coredata"
)

const (
	DefaultGarbageCollectionInterval = 1 * time.Hour
)

type (
	GarbageCollector struct {
		pg       *pg.Client
		interval time.Duration
		logger   *log.Logger
	}

	GarbageCollectorOption func(*GarbageCollector)
)

func WithGarbageCollectionInterval(interval time.Duration) GarbageCollectorOption {
	return func(gc *GarbageCollector) {
		gc.interval = interval
	}
}

func NewGarbageCollector(
	pgClient *pg.Client,
	logger *log.Logger,
	opts ...GarbageCollectorOption,
) *GarbageCollector {
	gc := &GarbageCollector{
		pg:       pgClient,
		interval: DefaultGarbageCollectionInterval,
		logger:   logger.Named("oidc.garbage_collector"),
	}

	for _, opt := range opts {
		opt(gc)
	}

	gc.logger = gc.logger.With(log.Duration("interval", gc.interval))

	return gc
}

func (gc *GarbageCollector) Run(ctx context.Context) error {
	gc.logger.InfoCtx(ctx, "oidc garbage collector starting")

	if err := gc.cleanup(ctx); err != nil {
		gc.logger.ErrorCtx(ctx, "cannot run initial cleanup", log.Error(err))
	}

	ticker := time.NewTicker(gc.interval)
	defer ticker.Stop()

	for {
		select {
		case <-ctx.Done():
			gc.logger.InfoCtx(ctx, "oidc garbage collector shutting down")
			return ctx.Err()
		case <-ticker.C:
			if err := gc.cleanup(ctx); err != nil {
				gc.logger.ErrorCtx(ctx, "cannot run periodic cleanup", log.Error(err))
			}
		}
	}
}

func (gc *GarbageCollector) cleanup(ctx context.Context) error {
	now := time.Now()

	return gc.pg.WithTx(
		ctx,
		func(ctx context.Context, tx pg.Tx) error {
			var state coredata.OIDCState

			deleted, err := state.DeleteExpired(ctx, tx, now)
			if err != nil {
				return fmt.Errorf("cannot delete expired oidc states: %w", err)
			}

			gc.logger.InfoCtx(
				ctx,
				"oidc garbage collector cleaned up expired states",
				log.Int64("deleted", deleted),
			)

			return nil
		},
	)
}